#include <stdio.h>
#include <string.h>

int main()
{
    FILE *fp = fopen("log.txt","wb");
    const char *msg = "linux so easy\n";
    fwrite(msg,1,strlen(msg),fp);
    fseek(fp,6,SEEK_SET);
    const char *app = "is so easy\n";
    fwrite(app,1,strlen(app),fp);

    fclose(fp);
    return 0;
}
